The primary objective of this study is to determine the doses of VPA-985, a vasopression receptor type 2 antagonist, which safely and effectively increases serum sodium in patients with hyponatremia from any etiology. In addition, we want to determine whether the use of VPA-985 will be associated with improvements in clinical variables, such as reduction in edema, improvement in neurocognitive function and a reduction in thirst. Terminated by sponsor due to lack of enrollment.